Conventionally, inkjet printers have been used today in diverse industrial and other applications. Inks typically used in the inkjet printers include ultraviolet-curable inks that are curable by being irradiated with ultraviolet light.
Some of the inkjet printers may be operable to change the finished condition of a printed matter by changing the duration of time from ejection of the ultraviolet-curable ink until irradiation of ultraviolet light. To be specific, when the ink that just landed on a print medium is immediately irradiated with ultraviolet light, the ink may be cured before dots of the ink are flattened. Thus, a resulting printed matter may have a matte finish with less glossy. When the ultraviolet irradiation starts after time is passed that is long enough to flatten dots of the ink that landed on the print medium, the ink may be cured after the dots are adequately flattened. Then, a resulting printed matter may have a glossy finish (for example, Japanese Unexamined Patent Publication No. 2015-214133).